Preparative Chromatography - Alternative Preparative Techniques > The Moving Bed Continuous Chromatography System > The Continuous Moving Process for the Isolation of Pure Acetylene Using Gas-Solid Chromatography > Page 47

Consequently, if there are two solutes (S1) and (S2) which are continuously fed on to the center of the column, having retention volumes Vr(1) and Vr(2), respectively,

then if

one solute (S2) will be eluted with the mobile phase at the end of the column and the other (S1) will be eluted with stationary phase and support at the front of the column.

The basic principles given above will apply to all moving bed or simulated moving bed systems irrespective of the complex nature of the experimental design.

The Continuous Moving Process for the Isolation of Pure Acetylene Using Gas-Solid Chromatography

The moving bed process described in 1956 by Freund et al. (10) was developed to isolate pure acetylene from the gaseous product obtained from methane oxidation. The actual feed mixture contained 8-9% of acetylene, 4-5% of carbon dioxide, 4-5% of methane, 25% of carbon monoxide, and about 50% of hydrogen.

The apparatus shown in figure 24 produces relatively pure acetylene as a direct product. The upper section is cooled with water to reduce the temperature of the carbon and allow the strong adsorption of acetylene, which takes place in the second section. The lighter gases are eluted at the top of the adsorber, (the top product). The cooled absorbent containing acetylene and carbon dioxide is heated and the carbon dioxide is first desorbed and collected as the upper product. As the adsorbent moves into a hotter part of the stripper section, the acetylene is desorbed and collected as the lower product. The product had a purity of about 98%.